Are those hand poses already defined? Is pinched for example already defined? If so, where is the list of defined hand poses?
Hand pose detection
You will need to apply some heuristic to determine what gesture can be inferred from the hand pose information. For example, the HandPose sample checks the distance between the thumb tip and the index finger tip to determine if the fingers are in a "pinched" state or not. You may also be able to train a machine learning model to classify the gesture based on hand pose input data.